Adding a color for the checkbox

[hopha95]

Users should be able to change the color of the default check box, in case they don't want to include new images in their source code.

Sample code snippet:

<CheckBox onClick={this.onClick.bind(this)}
        isChecked={this.state.isSelected}
        checkBoxColor={'blue'}
        style={{alignSelf: 'center', position: 'absolute', right: 25}}/>

[BasitAli]

This is now outdated. tintColor needs to be applied through style.

[acomito]

@BasitAli what do you mean? checkBoxColor worked for me.

It should be added to docs though.

[BasitAli]

@acomito it didn't at the time of the comment and I made a pull-request that has since been merged :).